And sensitizing photographic paper



ma my WILLIAM S. LUKENBACH, OF. NEWPORT, PENNSYLVANIA.

Letters Patent No. 89,488, (lated April 27, 1869.

APPARATUS POR FLOWING- AND SENSITIZING PHOTOGRAPHIC PAPER, &c.

The Schedule referred to in these Letters Patent and making part of the same.

To all whom it may concern:

Be it known that LWILLIAu S. LUKENBACH, of Newport, in the county of Perry, in the State of Pennsylvania, have invented a new and improved Mode, or Process of-Sensitizing Photographic Paper; and I do hereby declare that the following is a full and exact description thereof, reference being had to the accompanying drawing, and to the letters of reference marked thereon.

The nature of my invention consists in sensitizing either albumeuized or plain photographic paper, by pouring, or flowing over it a solution of nitrate of silver;7 made in strength of from fifty to sixty grains of said nitrate of silver, to one ounce of water, instead of oating the paper in a dish containing the silver and other chemicals.

My invention may be styled The Flowing-Process of Sensitizing Photographic Paper.

To enable others skilled in the art to make and use my invention and process, I will proceed to describe its construction and operation.

I make a light wooden frame, as shown hy A, suliiciently large to sensitize a full-sized sheet of photographic paper. Said paper, in size, is uniform, being seventeen and a half inches Wide, by twenty-three inches long. p

To enable me to place a sheet of paper of this size on my frame, I construct said frame twenty-two inches in width, by twenty-eight inches in length, allowing iive inches each way forthe edge of the frame, and the springs, or fastenings, hereinafter' described.

One side of this frame I cover with a thin cloth of muslin, or other light material, B, (the color of which is immaterial, though it 'were better, black,) securely fastened to the edges by glue or tacks, and stretched across the frame so as to allow it to become alittle concave in the centre.

At' each of the four corners of this frame, I attach, by means of elastic cords, as shown by C G C C, a spring clothes-pin, or other appliance of a si mil-ar nature, as shown by D D D D, each of which extends from the edge of the frame toward the centre, about three inches.

At each ofthe four corners, a small tin keeper may be placed, to secure the springs, or catches, and keep them ofi` the cloth covering of the frame, when not in use, as shown at E.

The elastic cords may be dispensed with, and the catches used without being fastened to the frame.

I take a sheet of photographic paper, and turn up the edges all around from one-eighth to onc-half of :in inch, so as to form a square hollow dish, as shown by F. This I place on the cent-re of the cloth covering the frame, and secure, in the spring-catches D, each per. This is done by moving the frame gently from side to side. I then loosen the springs D at three of the corners of the paper, and, by lowering or movingV the paper dish to the edge, or corner of the ii'ame A, I pour back into the graduate or bottle the solution of silver which has not been taken up by the paper.

The paper is then hung up in a dark room to dry, and when perfectly dry is ready for use in printing.

This process may be used in sensitizing either a fullsized sheet of paper, or any portion of it, and the frame may be made of any size to suit the wants of 'the operator.

The back, or outer side of the frame, may be covered with thin boards or pasteboard, which can be used as a table, upon which to fold the paper, or it may be left uncovered.

The advantages of my invention or process over the methods now in use, are- First. It dispenses with the use of the dishes now in use, which are expensive, and which, unless perfectl clean, and free from all foreign substance, such as dust, &c., destroy and render worthless the silver poured into them.

Second. These frames are simple, and any photographer can construct one. y

Third. No other chemicals are used in sensitizing the paper but the solution `of nitrate of silver, made as aforesaid.

Fourth. It requires less silver to sensitize the paper, than by any other method known, three ounces being suiiicient to sensitize a full-sized sheet of paper and when used and poured back into the bottle, it has lost but little of its strength, while in a iioating-bath it requires from a pint toa quart of nitrate of silver7 solution, for a tub large enough to sensitize the samesized sheet of paper, and the paper remaining in the bath for some time, absorbs more ofthe silver. A portion also adheres to the sides of the dish, which is a. loss to the operator. v

Fifth. The nitrate of silver does not so readily disc-olor by this process, and, in using paper of some makes, not at all.

Sixth. It requires less time to sensitize the paper by this process.

Seventh. The paper thus sensitized dries much quicker, is more sensitive, and, when dry, is ready for What I claim as my invention, and desire to scour@ use, thus dispensing entirely with the filming-process l by Letters Pat-ent, is-

now used. v The frame A, for the purpose of sensitizing photo- Eighth. The paper retains the alhumen-gloss better graphic paper, or other material, either nlbumenized or wheu'thus prepared. plain, by the use of :t solution of nitrate o'silver, in

Ninth. Any desired tone is more easily and readily the flowing-process, orfor flowing with other solutions, obtained, especially the sepia tone so much sought substantially' in the manner, and for the purposes set after. forth.

Tenth. It requires less chloride of gold to tone the W. S. LUKENBACH. same amount oi'priut-s, by my process, and the paper lVitnesses: thus prepared hits greater body and more intensity, A. O. H. WEBSTER,

and will print in much less time. A. C. KLINK. 

